This invention relates to a pressure-sensitive and conductive rubber, wherein a liquid organic substance having compatibility is impregnated with an electrically conductive rubber.
There are being produced various kinds of pressure-sensitive and conductive materials formed by mixing a high-molecular elastic material such as rubber, plastic, etc. or a thermoplastic synthetic resin with a conductive filler such as a carbon black, a conductive metal or the like.
Further, there is known a pressure-sensitive material as an anisotropic conductor. It is produced by the step that the particles or powders of a conductive ferromagnetic metal are dispersed in and mixed with such high-molecular elastic material or thermoplastic synthetic resin, subsequently such a mixture is magnetized in a flow condition and the metallic particles are disposed along a magnetic field. Thus, there is produced a pressure-sensitive and conductive material called anisotropic conductor, in which electrical conductivity is given in a certain direction.
However, when adjusting the pressure-electrical resistance property of the pressure-sensitive and conductive material of this kind to a desired range, the inconvenience is that the mixture ratio of the metallic or carbon particles, their particle size or arrangement must be changed. Further, a liquid silicone rubber is normally used so as to meet a desired property and quality, but since its specific gravity is different from that of the conductive metallic or carbon particles to be mixed with the above liquid silicone rubber, a sendimentation phenomenon of the particles arises when crosslinking the rubber due to a difference of the specific gravity, thereby a uniform dispersion of the particles is not obtained.